材料科学与工程基础1

1、StructureA description of the arrangement of atoms ,as seen at different levels of detail.SynthesisRefers to how materials are made from naturally occuring or man-made chemicals.ProcessingMeans how materials are shaped into useful components to cause changes in the properties of different materials.

2、Figure Application of the tetrahedron of materials science and engineering to sheet steels for automotive chassis. Note that the microstructure-synthesis and processing-composition are all interconnected and affect the performance-to-cost ratioComposition;Strength;Weight;Energy absorption properties

3、;Malleability (formability)Strength-to-weight ratio is the strength of a material divided by its density; materials with a high strength-to-weight ratio are strong but lightweight.Figure Application of the tetrahedron of materials science and engineering to semiconducting polymers for microelectroni

4、cs. rubst 结实的；耐用的；坚固的 Synthesis and processing How can pure, homogeneous, and fine powders of well-defined stoichiometry be made? How do we make long lengths of wires?Figure Application of the tetrahedron of materials science and engineering to . Note that the microstructure-synthesis and processing

5、-composition are all interconnected and affect the performance-to-cost ratio What is the current carrying capacity? What is the cast of cooling and fabrication?Microstructure What features of the structure limit the current carrying capacity? What is the texture of the material?Composition YBa2Cu3O7

6、-x YBa2Ca3Cu4O11 YSr2Ca2Cu3O10Performance Cast Tetrahedron of MSE Composition Synthesis and processing Microstructure performance/costApplication OF Tetrahedron :a sample product ceramic superconductors invented in 1986 (1)DISCOVERY(2)LIMITATION(3)IMPROVEMENT(4)SOLUTION(5)BRITTLE(6)SOLUTION Biomater

7、ials 生物功能性生物功能性(biofunctionability )和生物相容性(biocompatibility ) metallic,ceramic, polymer materials finger joint teeth 手指关节Figure Representative strengths of various categories of materials聚醚酮树脂聚乙烯环氧树脂芳纶纤维聚酰亚胺 聚酯纤维 ，涤纶StructuralSteel Aluminum alloysConcrete FiberglassPlastic, WoodSmart materialsPZTSha

8、pe-memory alloysMR fluidPolymer gelsOpticalMaterialsSiO2, GaAsGlasses, Al2O3YAG, ITO Fe, Fe-Si, NiZn And MnZn ferrites;Co-Pt-Ta-Crg-Fe2O3UO2, Ni-Cd, ZrO2, LiCoC2, Amorphous Si:HSi, GaAs, Ge, BaTiO3, PZT, YBa2Cu3O7, Al,Cu, W, ConductingpolymerBiomedical Hydroxyapatite羟磷灰石 Titanium alloys,Stainless st

9、eelsShape-memory alloysPlastics, PZTAerospace C-C composites,SiO2, Amorphoussilicon, Ai-alloysSuperalloysMagneticMaterialsEnergy Technology &EnvironmentalElectronic Materials Figure Functional classification of materials. Notice that metals, plastics, and ceramics occur in different categories.

10、A limited number of examples in each category is providedClassification ofFunctionalMaterialsITO: In2O3-SnO2MR: magnetorheologyPZT: lead zicornium titanateYAG: yttrium aluminum garnet(Y3Al5O12)磁流体铟-锡压电陶瓷(锆钛酸铅) (Y3Al5O12)(Y3Al5O12)SEM5 nmMSEXRD, TEM Optical 19 透明度: -氧化铝因其结构不同而透明、半透明、不透明Adapted from F

11、ig. 1.2,Callister 7e.(Specimen preparation,P.A. Lessing; photo by S. Tanner.)单晶(transparent)多晶：低孔隙度（translucent; semitransparent） 多晶：高孔隙度 （opaque ）Figure Increasing temperature normally reduces the strength of a material. Polymers are suitable only at low temperatures. Some composites, special alloy

12、s, and ceramics, have excellent properties at high temperaturesFigure A section through a jet engine. The forward compression section operates at low to medium temperatures, and titanium parts are often used. The rear combustion（尾部燃烧）（尾部燃烧） section operates at high temperatures and nickel-based supe

13、ralloys are required. The outside shell experiences low temperatures, and aluminum and composites are satisfactory. (Courtesy of GE Aircraft Engines.)Figure A variety of complex ceramic components, including impellers（叶轮）（叶轮） and blades, which allow turbine engines to operate more efficiently at hig

14、her temperatures. (Courtesy of Certech, Inc.)Figure Polymers are used in a variety of electronic devices, including these computer dipswitches, where moisture resistance and low conductivity are required. (Courtesy of CTS Corporation.)Figure Integrated circuits for computers and other electronic devices rely on the unique electrical behavior of semiconducting mat